YSI 2700 SELECT, User Manual

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4-5
!
This is a direct reading of dextrose in solution at the enzyme sensor. The enzyme Glucose
Oxidase is immobilized in the YSI Dextrose Membrane.
De O
2 Glu Oxidase
H
2
O
2
+ D-Glucono-
δ
-Lactone
System Buffer YSI 2357
Calibrator Std YSI 2776 (2.50 g/L dextrose)
Linearity Std YSI 1531 (9.00 g/L dextrose)*
Black Probe YSI 2365 (Dextrose Membrane)
White Probe n/a **
Sample Size 25
µ
L
Cal Station Station #1 Cal Well
Black Probe Parameters
Chemistry
Dextrose
Unit of Conc g/L
Cal value 2.50
End Point 30 sec
Note: See Appendix A if concentration unit conversion is required.
* For applications requiring linearity performance to 25.0 g/L, YSI 2777 (25.0 g/L dextrose)
may be used as a linearity standard provided the sample size is 10
µ
L.
** If you have a dual channel unit, either Black or White, or both Black and White probes can
be configured for this chemistry.
Special Considerations:
» If sample dilution is required, use reagent water or 2357 buffer.
» If a solution must be prepared from solid dextrose, use the following diluent and allow
about 15 minutes before measuring the sample. This is required for dextrose, which
must equilibrate alpha and beta anomers (mutarotational equilibrium). If your reading
is lower than expected, you may need to wait slightly longer for equilibration.
Diluent: 40 g/L NaH
2
PO
4
10 g/L Na
2
HPO
4
Reagent water
Both heat and the presence of phosphate accelerate mutarotational equilibration.